44 research outputs found
Life cycle assessment (LCA) of electricity generation from rice husk in Malaysia
AbstractThis paper evaluated the life cycle analysis (LCA) of electricity derived from rice husk combustion in the Malaysia rice mills. Due to environment and security constraint cause by fossil fuel, biomass like rice husk becomes an attractive solution to look at. However, the environment profile of the electricity production from rice husk must be assessed to ensure it environment safety. The unit processes that make up the system are the paddy production, transportation to the rice mill, rice mill processing and combustion of rice husk to generate electricity. This study used functional unit as, 1.5MWh of electricity generating at the energy plant. The result show transportation contributes more to climate change compare to other process. Then, the characterized data from rice huskderived electricity is compared with coal and natural gas derived electricity. The results indicate the performance of rice husk derived-electricity is better in the aspect of environment impact parameters
Cost-benefit analysis and emission reduction of energy efficient lighting at the Universiti Tenaga Nasional.
This paper reports the result of an investigation on the potential energy saving of the lighting systems at selected buildings of the Universiti Tenaga Nasional. The scope of this project includes evaluation of the lighting system in the Library, Admin Building, College of Engineering, College of Information Technology, Apartments, and COE Food court of the university. The main objectives of this project are to design the proper retrofit scenario and to calculate the potential electricity saving, the payback period, and the potential environmental benefits. In this survey the policy for retrofitting the old lighting system with the new energy saving LEDs starts with 10% for the first year and continues constantly for 10 years until all the lighting systems have been replaced. The result of the life cycle analysis reveals that after four years, the selected buildings will bring profit for the investment
Prioritising urban green spaces using accessibility and quality as criteria
Urban green spaces are a critical component of cities, providing environmental, social, cultural, and economic benefits. To support smart(er) decisions by city planners and managers, this study aims to investigate how open data sources could be integrated into urban green space management. Specifically, it proposes a novel GIS-based method to prioritise urban green space in a resource-constraint scenario so that social benefits are maximised. To quantify the social benefits, the methodology is based on the WHO indicator, which recommends access to at least 0.5-1 ha of green space within 300 metres\u27 linear distance to all the city residents. The approach assigns each urban green space an \u27accessibility score\u27 based on its significance in the city, and a \u27quality score\u27 based on its performance on different quality parameters (size, greenness, quietness, and safety). Urban green spaces are ranked with respect to these two scores, enabling to prioritise spaces under resource constraints such as water shortage, limited staff, or budget. This approach is demonstrated through a case study on a mid-size German city and is transferable to other cities worldwide with varying weightage factors
Water distribution system design integrating behind-the-meter solar under long-term uncertainty
Water distribution systems (WDSs) are important urban water infrastructure supporting a wide range of human activities. Due to the significant amount of energy consumed by the WDS throughout its lifespan, the operation of WDSs may have a significant impact on the environment, affecting the sustainable development of cities into the future. Behind-the-metre (BTM) solar photovoltaic (PV) system integration has been considered an effective way to reduce the impact of WDSs on the environment. However, solar PV technology is developing rapidly. Combined with long-term changes in water demand driven by population growth and urbanisation, the design of a WDS considering BTM solar has become a more challenging task. In this study, the co-design of WDS integrating BTM solar PV systems under changing future conditions in terms of water demand and solar PV technology development is investigated. It has been found that the BTM solar PV system and the potential development in solar PV technology effectively improve the robustness of WDS design under uncertain future water demand. The outcomes of this study can be extended to guide infrastructure design to provide sustainable infrastructure for future cities, and therefore cities can continue to support human activities in deeply uncertain future.Jiayu Yao, Wenyan Wu, Angus R. Simpson, Behzad Rismanch
Chemically-Induced RAT Mesenchymal Stem Cells Adopt Molecular Properties of Neuronal-Like Cells but Do Not Have Basic Neuronal Functional Properties
Induction of adult rat bone marrow mesenchymal stem cells (MSC) by means of chemical compounds (β-mercaptoethanol, dimethyl sulfoxide and butylated hydroxyanizole) has been proposed to lead to neuronal transdifferentiation, and this protocol has been broadly used by several laboratories worldwide. Only a few hours of MSC chemical induction using this protocol is sufficient for the acquisition of neuronal-like morphology and neuronal protein expression. However, given that cell death is abundant, we hypothesize that, rather than true neuronal differentiation, this particular protocol leads to cellular toxic effects. We confirm that the induced cells with neuronal-like morphology positively stained for NF-200, S100, β-tubulin III, NSE and MAP-2 proteins. However, the morphological and molecular changes after chemical induction are also associated with an increase in the apoptosis of over 50% of the plated cells after 24 h. Moreover, increased intracellular cysteine after treatment indicates an impairment of redox circuitry during chemical induction, and in vitro electrophysiological recordings (patch-clamp) of the chemically induced MSC did not indicate neuronal properties as these cells do not exhibit Na+ or K+ currents and do not fire action potentials. Our findings suggest that a disruption of redox circuitry plays an important role in this specific chemical induction protocol, which might result in cytoskeletal alterations and loss of functional ion-gated channels followed by cell death. Despite the neuronal-like morphology and neural protein expression, induced rat bone marrow MSC do not have basic functional neuronal properties, although it is still plausible that other methods of induction and/or sources of MSC can achieve a successful neuronal differentiation in vitro
Low energy building retrofit: A review of objectives and solutions
Worldwide, the building sector is accountable for one-third of final energy consumption. This is expected to increase in the future. It is due to the continuing growth in demand for new buildings and the poor energy efficiency of the existing building stock. In developed countries, the ratio of new to old buildings is around 1% per year. According to the European Energy Performance of Buildings Directive Recast (Directive 2010/31/EU), optimal solutions towards low and near-Zero Energy Building (near ZEB) retrofit is of critical importance in order to achieve European Union (EU) climate and energy objectives. This has led to a large number of projects on deep building retrofit during the last 20 years. Each project has specific objective functions, depending on the adopted stakeholder’s perspective and the selected retrofit strategies are dictated by the objective functions set. This study investigates stakeholders (legislators, investors, owners and users), objectives and optimal retrofit strategies and their interrelationships. The focus is on residential buildings due to the significant opportunity for reducing their Greenhouse Gas (GHG) emissions. A matrix has been developed to classify information in order to facilitate comparison and apparent correlations to be identified. The expected outcome is the better understanding of stakeholders’ perspectives on financial, energy, GHG emissions, thermal comfort and the resulted optimal strategies
A review of Net Zero Energy Buildings with reflections on the Australian context
A Net Zero Energy Building (NZEB) is a term, subject to ambiguity, that could be used to describe a building with characteristics such as equal energy generation to usage, significantly reduced energy demands, energy costs equalling zero or net zero greenhouse gas (GHG) emissions. Despite lacking an authoritative definition of NZEBs, this relatively new emerging concept in Australia provides significant opportunities to reduce GHG emissions, energy usage and operational energy costs for buildings owners. This paper aims to explore the existing NZEB models, assess the progression of NZEB literature, identify key policies encouraging NZEB development and recognise potential areas of NZEB research
A review of micro hydro systems in urban areas: Opportunities and challenges
The modern layout and configuration of cities create power generation and storage possibilities through the urban water system. Surplus energy in water and wastewater networks has come to the researchers’ attention for exploitation as micro hydropower (MHP). Also, the gravitational potential energy of stored water on highrises makes them a sustainable option for distributed energy storage as micro pumped-storage (MPS). Many studies have investigated technical aspects and estimated capacity of urban micro hydro systems (UMHS) in urban infrastructures. However, there is no systematic review of relevant literature to signify challenges and opportunities of different urban infrastructures as UMHS, from economic, technical, and environmental viewpoints. Therefore, this article applied a reference-by-reference method to provide a systematic assessment and concept review of UMHS, including the characteristics, challenges, and drivers of potential sites for MHP and MPS development. Examining the challenges of real case studies worldwide identifies economic feasibility and energy generation reliability as obstacles in developing MPS and MHP, respectively. Nevertheless, overlooked opportunities are recognised that may accelerate UMHS proliferation. UMHS synergies, such as water saving and peakload shaving, are introduced as influential factors in the economic feasibility of the UMHS that can be achieved through deploying sustainable stormwater management strategies and considering real-time analysis in the volatile energy market. Furthermore, simulation-optimisation tools are concisely presented for both the design and operation stages. Finally, some future research directions are offered to clarify the role of urban UMHS in addressing water and energy issues as individual systems or integrated into other decentralised energy sources.Arezoo Boroomandnia, Behzad Rismanchi, Wenyan W
Optimisation of a seasonal thermal energy storage system for space heating in cold climate zones
The parameter optimised for a seasonal thermal energy storage (STES) system based on life cycle cost (LCC) is a unique investigation. Although STES with ground coupled heat pump (GCHP) and solar collector system have been verified and validated in other countries, the result cannot be used for particular cold climates because the performance of the system is highly climate sensitive. Therefore, this study intends to fill the knowledge gap by identifying optimum sets of system variables for four selected cities in cold climate zones
Ten questions concerning green buildings and indoor air quality
This paper investigates the concern that green buildings may promote energy efficiency and other aspects of sustainability, but not necessarily the health and well-being of occupants through better indoor air quality (IAQ). We ask ten questions to explore IAQ challenges for green buildings as well as opportunities to improve IAQ within green buildings and their programs. Our focus is on IAQ, while recognizing that many factors influence human health and the healthfulness of a building. We begin with an overview of green buildings, IAQ, and whether and how green building certifications address IAQ. Next, we examine evidence on whether green buildings have better IAQ than comparable conventional buildings. Then, we identify so-called green practices and green products that can have unintended and unfavorable effects on IAQ. Looking ahead, we offer both immediate and longer-term actions, and a set of research questions, that can help green buildings to more effectively promote IAQ. This article supports a growing recognition of the importance of IAQ in green buildings, and the opportunities for improvements. As the World Green Building Council [95] and others have emphasized, people are the most valuable asset of organizations, and efforts to improve IAQ can improve health, well-being, productivity, and profitability